import React, { Component } from 'react'
import store from '../../redux/store'
// 引入actionCreator，专门用于创建action对象
import {createIncrement, createDecrement} from '../../redux/count_action'

export default class Count extends Component {

state = {carName: "捷途旅行者"}

// componentDidMount(){
//   // 检测redux中状态的变化，只要变化，就调用render
//   store.subscribe(()=>{
//     console.log("store被调用了！")
//     // this.render() 这个不行，手动调不了
//     this.setState({}) // 会触发render方法
//   })
// }

increment = () => {
  const {value} = this.selectNumber
  // 通知redux加Value
  store.dispatch(createIncrement(value * 1))
}

decrement = () => {
  const {value} = this.selectNumber
  // 通知redux加Value
  store.dispatch(createDecrement(value*1))
}

incrementIfOdd = () => {
  const {value} = this.selectNumber
  const count = store.getState()
  if(count % 2 !=0){
    store.dispatch(createIncrement(value * 1))
  }
}

incrementAsync = () => {
  const {value} = this.selectNumber
  const count = store.getState()
  setTimeout(() => {
    store.dispatch(createIncrement(value * 1))
  }
  , 2000)
}



  render() {
    return (
      <div>
        <h1>当前求和为：{store.getState()}</h1>
        <select ref={c => this.selectNumber = c }name="" id="">
          <option value="1">1</option>
          <option value="2">2</option>
          <option value="3">3</option>
          <option value="4">4</option>
          <option value="5">5</option>
        </select>&nbsp;
        <button onClick={this.increment}>+</button>&nbsp;
        <button onClick={this.decrement}>-</button>&nbsp;
        <button onClick={this.incrementIfOdd}>当前求和为基数就加</button>&nbsp;
        <button onClick={this.incrementAsync}>异步加</button>
      </div>
    )
  }
}
